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The present invention generally relates to filters within a baghouse or dust collector and more particularly to an air filter cartridge having a reusable mounting plate for securing the filter within the baghouse.
Filter apparatus, such as baghouses, are commonly used for removing particulates and aerosols from the air in industrial environments. Baghouses typically include two large chambers, or plenums, that are divided by a tube sheet. The filter cartridges, preferably containing fabric filtration elements, are secured to the tube sheet at one end to suspend the cartridge within the lower plenum. Fabric filter media having longitudinal pleatings are particularly effective for removing particulates. One such air filter cartridge is disclosed in U.S. Pat. No. 5,632,791.
Air containing particulates is forced into the first plenum by a forced air means such as a fan. The air passes from the first plenum to the second plenum via the air filter cartridges held by the tube (or pan) sheet. The particulates are retained on the outer surface of the fabric filter element of the cartridge filter, and the clean air is directed into the second plenum and exits the baghouse through an exhaust passageway.
Oftentimes, the baghouses are operated continuously for relatively long periods of time. As with most physical filtration media, the effectiveness of the filter media diminishes as particulates collect on the outer surfaces of the filter elements and restrict the airflow through the filters. To remove accumulation of particulate on the baghouse filters, air may be pulsed through the baghouse cartridge filters from the second plenum to the first plenum. The air pulses dislodge the particulates embedded on the exterior surface of the filter, and the loose particulates are removed from the first plenum. Accordingly, the effectiveness of the baghouse is greatly increased without having to frequently remove and replace the cartridges. One such apparatus for cleaning baghouse filters is disclosed in U.S. Pat. No. 5,837,017.
While the cleaning process significantly increases the life span of the filter elements, the filter cartridges must be replaced periodically. Accordingly, a number of systems have been used to releasably secure the filter cartridges in sealing engagement with the tube sheet. One such mechanism, disclosed in U.S. Pat. No. 4,322,231, utilizes a pair of longitudinal bars underlying the tube sheet. A metal mounting plate is integrally formed with the upper end of each filter cartridge. The mounting plate is slid along the bars and suspended therefrom. When the filter cartridges are in the proper position on the longitudinal bars, the bars are rotated so that a curvilinear surface on each bar forces the mounting plates into sealing engagement with the pan sheet. A gasket on each filter cartridge seals the cartridges to the pan sheet when the cartridges are locked in the operational position within the baghouse.
However, the cartridge filters used within this mounting system are costly to manufacture, in part, due to the costs of the raw materials that are discarded when the cartridges no longer effectively remove particulates from the air. Moreover, it is difficult and costly to form the mounting plate integrally with the filter cartridge, and is particularly difficult to manufacture an integral mounting plate sized to fit between the locking mechanism and tube sheet.
It is an object of the present invention to provide an air filter cartridge having a mounting plate to removably mount a filter cartridge in a baghouse.
In accordance with the foregoing and other objects evident from the following description of a preferred embodiment of the invention, a filter cartridge for use in a baghouse having a tube sheet is provided. The filter cartridge includes a tubular filter having opposite ends, a mounting cap and a reusable mounting plate. The mounting cap is secured to one end of the tubular filter and has a first surface and a ledge extending from the tubular filter. The mounting plate has an opening sized for receipt of the tubular filter. The ledge of the mounting cap overlies the mounting plate when the tubular filter is received within the opening, and the mounting cap is supported by the mounting plate to enable the first surface to engage the tube sheet when the baghouse is in operation.
In another aspect, a filter cartridge for use in a baghouse having a tube sheet and a locking mechanism is provided. The filter cartridge has a tubular filter with opposite ends, a mounting cap and a mounting plate. The mounting cap is secured to one end of the tubular filter and has a first surface and a ledge extending from the tubular filter. The mounting plate has an opening sized for receipt of the tubular filter. The ledge of the mounting cap overlies the mounting plate when the tubular filter is received within the opening. Thus, the mounting cap is supported by the mounting to enable the first surface to engage the tube sheet when the locking mechanism moves the mounting plate in a direction towards the tube sheet and the baghouse is in operation.
In yet another aspect of the present invention, a method for securing a filter cartridge in a filter apparatus (such as a baghouse) is provided. The method includes providing a reusable mounting plate having an opening, placing the filter cartridge within the opening of the plate and releasably securing the mounting plate to a tube sheet within the baghouse.
By providing an air filter cartridge in accordance with the present invention, numerous advantages are achieved. For instance, the mounting plate may be re-used with the replacement filter cartridges as the prior cartridges lose their utility. Also, the unique filter cartridge provides a compact and effective design wherein the combined height of the mounting cap and mounting plate is relatively thin. Moreover, the cost of production of the device of the present invention is significantly lower than filter cartridges having integral mounting plates of the prior art.